Examination of thin films in the ZrO2–SiO2 system by transmission electron microscopy and x-ray diffraction techniques

Abstract

The microstructure of thin films of ZrO2 and ZrO2–SiO2 formed by electron-beam coevaporation have been examined by x-ray diffraction and transmission electron microscopy. Results of these examinations suggest that films composed of 100% ZrO2 grow by the formation of tapered polycrystalline columns. Near the substrate the columns are of small diameter and contain a single crystalline phase, but at increasing distances from the substrate the column diameters increase and material with two crystalline phases occurs. Small additions of SiO2 to the film composition result in a smaller column diameter at a given distance from the substrate. Films with greater than 30% SiO2 by volume, which earlier had been shown to display an amorphous x-ray diffraction pattern, have been shown to display an amorphous electron diffraction pattern as well. The surfaces of the amorphous films are nearly featureless and are significantly smoother than the surfaces of 100% ZrO2 films.